Write the cations and anions present, if any, in the following:

(a) CH₃COONa (b) NaCl

(c) H₂ (d) NH₄NO₃

Calculate the formulae masses of the following compounds:

(i) Sodium oxide, Na₂O

(ii) Aluminium oxide, Al₂O₃

(Given: Atomic masses: Na = 23 u; O = 16 u; Al = 27 u)

Name the following compounds. Also write the symbols/formulae of the ions present in them:

(a) CuSO₄ (b) (NH₄)₂SO₄

(c) Na₂O (d) Na₂CO₃

(e) CaCl₂

Give the formulate of the compounds formed from the following sets of elements:

(a) calcium and fluorine

(b) hydrogen and sulphur

(c) nitrogen and hydrogen

(d) carbon and chlorine

(e) sodium and oxygen

(f) carbon and oxygen

What are (i) ionic compounds, and

(ii) molecular compounds? Give two examples of each type of compounds.